MONOGRAPH OF THE GENUS SAPERDA 7 1 



Saperda moesta Lee. 



This insect [pi. 7, fig. 5] confines its operations to the balsam 

 poplar or balm of Gilead so far as known, and occasionally it is 

 quite injurious to this tree. 1 



Life history. The beetles appear in June. Two sizes of larvae 

 in gall-like swellings from 1 to 2 inches apart and in shoots about 

 V2 inch in diameter were found by Mr Harrington in June. The 

 late Dr D. S. Kellicott bred Sciapteron tricincta Harr. 

 from enlargements in the branches and stems of the balm of 

 Gilead and the common willow 2 which were caused by this 

 species and its associate. Saperda concolor. Mr Saund- 

 ers states that he received a bundle of balm of Gilead twigs on 

 Mar. 25 which were infested with this insect. The larvae were 

 very thickly set in the branches, in many places not more than 

 an inch or two apart, and located chiefly at the base of the buds, 

 where the presence of the occupant was indicated by a swelling 

 in the branch which was surmounted by a dark brown patch of 

 partly decayed bark. The castings and debris of the borer were 

 of a light orange color and were pushed forward, stuffing the 

 swollen part. The whole length of the excavation made by each 

 larva did not usually exceed an inch, and so much of this was 

 filled with debris that the clear space left was very little larger 

 than its body. Mr Saunders describes the larvae as follows : 



Body above deep yellow, with a glossy surface, sprinkled with 

 very minute, short yellow hairs, invisible without a lens. Second 

 segment above and below a little deeper in color and more horny 

 looking than the other segments ; interspaces between segments 

 strongly indented. There was a depressed dorsal line not differ- 

 ent in color from the rest of the body, but sunken, and on each 

 side of it the projecting rings of the body were somewhat flat- 

 tened. Spiracles pale brown, rather small. Terminal segment a 

 little more hairy than the others. 



x Mr Charles Stevensen, of Montreal, kindly sent us some fresh galls 

 pf Saperda moesta, from which the illustrations were made and a 

 number of specimens reared. 



= Moesta probably caused the galls in balm of Gilead, and con- 

 color those in the willow. 



